The invention relates to a curved corner of a spacer frame of an insulating glazing, and further to a process for the production of the new corner.
A curved corner of this general type is known in the prior art, as disclosed in EP-OS No. 0 003 715. In this known corner, one disadvantage is that fillets are disposed between the incisions, which leads to undesired and uncontrollable deformations in the corner zone. These deformations may be, for example, concave or convex archings in the inside wall of the side walls thereof, so that there are no flat side surfaces provided in the region of the curved corner, for example, for receiving the surrounding butyl strips or similar sealing agents. Level surfaces, especially in the corner zone, however, are an important precondition for assuring the sealing, with the required quality, of the inner space of the insulating glazing against the outer atmosphere.
Level surfaces can be obtained, to be sure, in a curved corner according to the prior art, as disclosed in U.S. Pat. No. 3,380,145, in which mitering incisions are generated. However, the rigidity of the curved corner of this latter patent is very slight, because the corner zone is held exclusively with the outer wall. It is noted, that this slight rigidity considerably impairs the handling of the frame having such curved corners.
German Patent Application No. P 32 33 399.4 teaches that the abutting edges of the frame can be solidly joined by injecting a stopper and/or plug into the curved corner.